A following object-tracking device is known. The object-tracking device first performs matching processing in which an input image to each frame is matched to each of a plurality of template images obtained at different times. Thereafter, a region of the input image that is matched most with the template images is designated as a template matching position. By updating the template matching position as a new template image, an object is tracked even if the shape, for example, of the object being tracked changes. (Refer to patent document 1)    Patent Document 1: Japanese Laid Open Patent Publication No. 2001-60269